TWI534565B - Photographic photoreceptor for electrophotography and method of manufacturing the same - Google Patents

Description

Photographic body for electrophotography and method of producing the same

The present invention relates to a photoreceptor for electrophotography used in an electrophotographic printer, a photocopier, a facsimile machine, etc. (hereinafter also referred to simply as "photoreceptor"), and a method for producing the same, and more particularly to improvement by an additive A photoreceptor for electrophotography having excellent printing durability or gas resistance and a method for producing the same.

In general, a photoreceptor for electrophotography requires a function of maintaining surface charge in a dark place, a function of generating light by light, and a function of receiving light by light. The photoreceptor includes, for example, a photosensitive layer having a single layer in which a single layer has such a function, a so-called single-layer type photoreceptor, and a photoreceptor layer having a photosensitive layer which is mainly laminated There are layers that participate in charge generation, and layers that participate in the retention of surface charges in the dark and charge transport during light reception.

According to the image formation using the electrophotographic method of the photoreceptor for electrophotography, for example, the Carlson method can be applied. The image formation in this manner is formed on the surface of the charged photoreceptor by electrostatic charging of the photoreceptor in a dark place, a character or a pattern of the original, and the electrostatic image formed by the toner The developed and developed toner images are transferred and fixed to a support such as paper. The photoreceptor after the transfer of the toner image can be reused after removing residual toner or removing electricity.

For the material of the above-mentioned electrophotographic photoreceptor, for example, selenium and selenium can be used. An inorganic photoconductive material such as an alloy, zinc oxide or cadmium sulfide is dispersed in a resin binder, or a poly-N-vinylcarbazole, a 9,10-nonanediol polyester, a pyrazoline, an anthracene, a An organic photoconductive material such as styrene, butadiene, benzidine, phthalocyanine or a disazo compound is dispersed in a resin binder, or may be subjected to vacuum evaporation or sublimation.

In recent years, with the increase in the number of printed sheets in the office and the rapid development of light-duty printers due to electrophotography, the printing devices for electrophotographic devices are increasingly required to have high durability and high sensitivity, and High speed responsiveness. In addition, it is strongly required that the influence of gas such as ozone or NOx generated in the device is small, and the variation in image characteristics due to fluctuations in the use environment (room temperature, humidity) is small.

However, at this stage, the conventional photoreceptor does not necessarily sufficiently satisfy the required characteristics, and the following problems can be enumerated.

For example, regarding wear resistance, there are the following problems. In recent years, not only monochrome printing printers or facsimile machines, but also color printing machines, high-speed printers have become popular due to the introduction of tandem development methods. In particular, in color printing, in addition to high resolution, the height of image position accuracy plays an important role in the required specifications. Due to the accumulation of the number of printed sheets, the surface of the photoreceptor may be worn by friction with paper or various rollers, scrapers, etc., and the greater the degree of wear, the more difficult it is to print high resolution and high image position accuracy. Image. So far, many discussions have been conducted to improve the wear resistance, but it has not yet reached a sufficient level.

Further, as far as the gas generated in the device is concerned, for example, there is ozone. Ozone is generated by a charging device or a roller charger for corona discharge, When ozone is left in the apparatus or the like, and the photoreceptor is exposed to ozone, the organic substance constituting the photoreceptor is oxidized to destroy the original structure, and the photoreceptor characteristics are remarkably deteriorated. Further, since ozone causes nitrogen in the air to be oxidized to become NOx, this NOx changes the organic substance constituting the photoreceptor.

The deterioration of the characteristics caused by such a gas not only erodes the outermost layer itself of the photoreceptor but also has an adverse effect due to the inflow of gas into the inside of the photosensitive layer. The outermost layer of the photoreceptor itself, although somewhat different, is removed by friction with the various members described above, but when a harmful gas flows into the inside of the photosensitive layer, the organic substance in the photoreceptor may be damaged in its structure. Therefore, it is a problem to suppress the inflow of harmful gases. In particular, in a color electrophotographic apparatus in which a plurality of photoconductors are connected in series, a difference in the degree of influence of gas due to a position of a drum in the apparatus, etc., causes a change in color tone, and a generation band for a good image To hinder. Therefore, in the tandem type color electrophotographic apparatus, deterioration of characteristics due to gas can be said to be a particularly important subject.

For the improvement of the gas resistance, Patent Document 1 and Patent Document 2 disclose the use of an antioxidant such as a hindered phenol compound, a phosphorus compound, a sulfur compound, an amine compound, or a hindered amine compound. Further, Patent Document 3 proposes a technique using a carbonyl compound, and Patent Document 4 proposes a technique using a benzoate-based or salicylate-based ester compound. Further, Patent Document 5 proposes that by using an additive such as biphenyl or the like and a specific polycarbonate resin, Patent Document 6 proposes a combination of a specific amine compound and a polyarylate resin, and Patent Document 7 proposes a polyarylate resin and A combination of compounds having a specific absorbance, which respectively enhances gas resistance. However, these technologies are still not A photoreceptor exhibiting sufficient gas resistance is obtained, or even if it exhibits satisfactory characteristics against gas resistance, it is not considered to improve abrasion resistance, and other characteristics (potential stability such as image memory or brush resistance) ), it has not yet reached satisfactory results.

Further, Patent Document 8 discloses that, under the condition of combination with a charge transporting layer having a specific charge mobility, the oxygen permeability coefficient of the surface layer is set to be less than or equal to a predetermined value, whereby gas sensitization generated around the charger can be suppressed. The influence of the body. Further, Patent Document 9 discloses that abrasion resistance and gas resistance can be improved by setting the water vapor permeability of the photosensitive layer to a predetermined value or less, but this technique cannot be used if a specific polymer charge transporting substance is not used. The desired effect is obtained, and it is limited by the mobility or structure of the charge transporting substance, and thus it is not possible to sufficiently respond to various electrical characteristics.

Further, Patent Document 10 discloses that a specific diester compound having a melting point of 40 ° C or less is used in the photosensitive layer, and a single-layer type electrophotographic photoreceptor excellent in gas resistance can be provided. However, when a substance having a low melting point is added to the layer at this time, the added photoreceptor is in contact with the used toner cartridge or the part of the apparatus body for a long time, and the compound sometimes permeates the other part of the contact. In the case, a so-called leak occurs and a defect occurs in the image, and a sufficient effect cannot be exerted.

Regarding the change in characteristics of the photoreceptor in the use environment, first, the deterioration of the image characteristics in a low-temperature and low-humidity environment is listed. In other words, in a low-temperature and low-humidity environment, generally, the sensitivity of the photoreceptor is lowered, and the deterioration of the image density or the deterioration of the image quality in the halftone image is deteriorated. Obviously. In addition, sometimes as the sensitivity characteristics deteriorate, Image memory has also become remarkable. When this phenomenon is printed, the image is recorded for the first time in the drum, and the image recorded by the latent image becomes a state in which the potential is changed after the second rotation of the drum, especially when printing a halftone image. It is unnecessary to print to cause deterioration of the image. Especially in the low-temperature and low-humidity environment, there are many examples in which the negative-type memory of the shading of the printed image can be clearly seen.

Next, the deterioration of image characteristics in a high-temperature and high-humidity environment is listed. That is, in a high-temperature and high-humidity environment, generally, the charge movement speed in the photosensitive layer is larger than that at normal temperature and normal humidity, so an excessive increase in the printing density or a minute black dot in the blank image (fog point) can be observed. ) and so on. An excessive increase in the printing density causes an increase in the amount of toner consumption, and in addition, the single point diameter becomes large and causes the fine gray tone to be destroyed. Further, regarding the image memory, as opposed to the low-temperature and low-humidity environment, the positive type memory of the concentration of the direct reaction print image is significantly observed.

The deterioration of the characteristics caused by this temperature and humidity condition is usually the cause of moisture absorption or desorption of the resin binder or the charge generating material in the surface layer of the photosensitive layer. On the other hand, as disclosed in Patent Document 11 or Patent Document 12, a specific compound is added to the charge generating layer, or Patent Document 13 uses a specific polycarbonate-based polymer charge transporting substance in the surface layer, and various materials have been studied so far. However, it is possible to suppress the influence of temperature and humidity conditions on the photoreceptor, and materials which can sufficiently satisfy various characteristics have not been found so far.

Further, the technique disclosed in Patent Document 14 can eliminate the problem of deterioration in characteristics caused by the above-described temperature and humidity conditions, but the wear resistance is still insufficient. Furthermore, Patent Document 15 discloses that it can be used as an optical material. The dialantane adamantane dicarboxylate used as a raw material of the resin of the material or the electrical material is not fully investigated for the compound having an adamantane structure as an additive for the photoreceptor. Further, Patent Document 16 discloses a photoresist composition containing a compound having an adamantane structure. Further, Patent Document 17 discloses a photoresist composition containing at least one compound having two or more adamantyl skeletons in one molecule. Patent Document 18 discloses a carboxylic acid derivative having an adamantane structure, and Patent Document 19 discloses a novel adamantane carboxylate compound, and none of these documents fully utilizes this compound as an additive in a photoreceptor. Review. Patent Document 20 discloses an electrophotographic photoreceptor having a polymer compound having a specific adamantane structure in a photosensitive layer, and Patent Document 21 discloses an electrophotographic photoreceptor provided with a photosensitive layer containing a specific adamantane-based compound, but such an image is disclosed. Still not enough.

[Advanced technical literature] [Patent Literature]

[Patent Document 1] JP-A-57-122444

[Patent Document 2] JP-A-63-18355

[Patent Document 3] JP-A-2002-268250

[Patent Document 4] JP-A-2002-287388

[Patent Document 5] JP-A-6-75394

[Patent Document 6] JP-A-2004-199051

[Patent Document 7] JP-A-2004-206109

[Patent Document 8] Japanese Patent Publication No. 08-272126

[Patent Document 9] JP-A-11-288113

[Patent Document 10] JP-A-2004-226637

[Patent Document 11] JP-A-6-118678

[Patent Document 12] JP-A-7-168381

[Patent Document 13] JP-A-2001-13708

[Patent Document 14] JP-A-2007-279446

[Patent Document 15] JP-A-60-100537

[Patent Document 16] JP-A-9-265177

[Patent Document 17] JP-A-2002-55450

[Patent Document 18] JP-A-2001-39928

[Patent Document 19] JP-A-2003-306469

[Patent Document 20] JP-A-4-174859

[Patent Document 21] Japanese Patent Publication No. 6-161125

[Summary of the Invention]

As described above, various techniques have been proposed in the past for improvement of the photoreceptor. However, the techniques described in these patent documents cannot satisfy the sufficient wear resistance and the characteristics of the photoreceptor, and at the same time, can sufficiently suppress the adverse effects of harmful gases or temperature and humidity on the photoreceptor, so Further improvement is required.

Accordingly, an object of the present invention is to provide a photoreceptor for electrophotography which can satisfy sufficient abrasion resistance and various characteristics as a photoreceptor, and which has little influence by a harmful gas or temperature and humidity environment, and a method for producing the same .

The inventors of the present invention have carefully examined the structure of the resin binder used for each layer of the photoreceptor, and have found that the voids generated by the molecular level when the resin binder forms a film become the cause of the above problems. Further, it has been found that the film contains a diadamantyl diester compound having a specific structure, and the effect of filling the void by the diadamantyl diester compound can solve the above problems.

As the resin used for the surface layer of the photoreceptor, polycarbonate or polyarylate resin or the like is mainly used at present. When the photosensitive layer is formed, various functional materials are dissolved in a solvent, and this is applied onto a substrate by dip coating or spray coating or the like to form a coating film. At this time, the resin binder forms a film in the form of a coating functional material, but a void having a size that cannot be ignored by a molecular level is generated. When the gap is larger, it is predicted that the abrasion resistance of the photoreceptor is deteriorated or the inflow and outflow of a low molecular gas such as a gas or water vapor is caused, and the electrical characteristics are deteriorated.

Therefore, by filling the voids formed by the resin binder with molecules of an appropriate size, a stronger film can be formed, the wear resistance can be improved, and the inflow and outflow of low molecular gases such as harmful gases or water vapor can be suppressed. A photoreceptor which does not deteriorate in electrical characteristics and image characteristics due to environmental changes is obtained. The inventors of the present invention have completed the present invention as a result of the above discussion.

In other words, the photosensitive system for electrophotography according to the present invention has a photoreceptor for electrophotography having at least a photosensitive layer on a conductive substrate, and is characterized by the aforementioned feeling. The optical layer contains the diadamantyl diester compound represented by the following general formula (I).

(In the general formula (I), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted carbon number of 1 to 6 Alkoxy group, aryl or heterocyclic group having 6 to 20 carbon atoms, each of l, m and n is an integer of 1 to 4, and U and W represent a single bond or a substituted or unsubstituted carbon number of 1 to 6 The alkyl group, V means an OCO group or a COO group, and when substituted, the substituent means a halogen atom, an amine group, an imido group, a nitro group, a nitroso group or a nitrile group.

Further, the photosensitive system for electrophotography of the present invention has a photoreceptor for electrophotography having at least a bottom layer on a conductive substrate, characterized in that the underlayer contains the diadamantyl diester compound represented by the above general formula (I).

Further, in the photosensitive system for electrophotography of the present invention, the electrophotographic photoreceptor having at least a charge generating layer on a conductive substrate, wherein the charge generating layer contains the diadamantyl group represented by the above general formula (I) Ester compound.

Further, the photosensitive system for electrophotography of the present invention has an electrophotographic photoreceptor having at least a charge transporting layer on a conductive substrate, characterized in that the charge transporting layer contains the bisadamantyl diester represented by the above general formula (I). Compound.

Furthermore, the photosensitive system for electrophotography of the present invention is on a conductive substrate A photoreceptor for electrophotography having at least a surface protective layer, characterized in that the surface protective layer contains the bisadamantyl diester compound represented by the above general formula (I).

In the present invention, the photosensitive layer may be a positively charged single layer type or a positively charged layered type. Further, the bisadamantyl diester compound preferably has a structure represented by the following formula (I-1). The amount of the bisadamantyl diester compound to be added is preferably 30 parts by mass or less based on 100 parts by mass of the resin binder contained in the layer containing the bisadamantyl diester compound.

Further, the method for producing a photoreceptor for electrophotography according to the present invention is a method for producing a photoreceptor for electrophotography comprising a step of applying a coating liquid forming layer on a conductive substrate, wherein the coating liquid contains The diadamantyl diester compound represented by the above general formula (I).

According to the present invention, the layer constituting the surface of the photoreceptor such as the photosensitive layer or the surface protective layer contains the bisadamantyl diester compound, and is not affected by characteristics such as the charge transporting material used, and the wear resistance can be improved. In addition, it is possible to prevent a harmful gas or water vapor from entering the inside of the photosensitive layer, and it is possible to realize a photoreceptor having little change in electrical characteristics and image characteristics due to environmental changes. Further, the laminated photosensitive system can suppress harmful gas or water vapor into the film by using the above diadamantyl diester compound in the charge generating layer or the underlayer. Inflow and outflow, a photoreceptor having little variation in electrical characteristics and image characteristics due to environmental changes can be realized. Therefore, according to the present invention, it is possible to improve the stability of electrical characteristics without affecting the type of the organic substance to be used or the temperature or humidity fluctuation of the use environment, and to realize an electrophotographic image which does not cause image damage such as image memory. Use a photoreceptor. The above bisadamantyl diester compound of the present invention has not been known in the past.

[Formation of the Invention]

Hereinafter, specific embodiments of the electrophotographic photoreceptor of the present invention will be described in detail using the drawings. The invention is not limited to the following description.

As described above, the photoreceptor for electrophotography can be roughly classified into a negatively-charged laminated photoreceptor and a positively-charged laminated photoreceptor which are functionally separated laminated photoreceptors, and a positively charged single layer. Type photoreceptor. Fig. 1 is a schematic cross-sectional view showing a photoreceptor for electrophotography according to an example of the present invention, wherein (a) shows an example of a functionally separated laminated electrophotographic photoreceptor having a negative charge, and (b) shows a positively charged single photo. An example of a photoreceptor for a layer type electrophotography, and (c) is an example of a photoreceptor for electrophotographic separation and electroluminescence. As shown in the figure, a negatively-charged laminated photosensitive system is sequentially laminated on a conductive substrate 1 with a bottom layer 2, a charge generating layer 4 having a charge generating function, and a charge transporting layer 5 having a charge transporting function. Layer 3. Further, the positive-charge type single-layer type photosensitive system sequentially laminates the underlayer 2, a single photosensitive layer 3 having both functions of a charge generating function and a charge transporting function on the conductive substrate 1. In addition, a positively-charged laminated photosensitive system is disposed on the conductive substrate 1 in sequence with the underlayer 2, which is provided with a charge transport function. The photosensitive layer 3 composed of the charge transport layer 5 and the charge generating layer 4 having a charge generating function. Regardless of any type of photoreceptor, the underlayer 2 may be provided as needed, and the surface protective layer 6 may be further disposed on the photosensitive layer 3. Further, the "photosensitive layer" in the present invention is a concept including both a laminated photosensitive layer in which a charge generating layer and a charge transporting layer are laminated, and a single layer type photosensitive layer.

In the present invention, it is important that at least one of the layers constituting the photoreceptor contains the bisadamantyl diester compound represented by the above general formula (I). That is, in the case where the conductive substrate has at least a photosensitive layer, particularly a photoreceptor having a positively-charged photosensitive layer, the desired effect of the present invention can be obtained by including the compound in the photosensitive layer. Further, the photosensitive system having at least the underlayer structure on the conductive substrate can obtain the desired effects of the present invention by including the compound in the underlayer. Further, the photosensitive system having at least a charge generating layer on the conductive substrate can obtain the desired effects of the present invention by including the compound in the charge generating layer. Further, a photosensitive system having at least a charge transporting layer on a conductive substrate can obtain the desired effects of the present invention by containing the compound in the charge transporting layer. Further, the electrophotographic photosensitive system having at least a surface protective layer on a conductive substrate can obtain the desired effects of the present invention by including the compound in the surface protective layer.

In any of the above-mentioned photoreceptors, the amount of the bisadamantyl diester compound used in the photosensitive layer is preferably 30 parts by mass or less based on 100 parts by mass of the resin binder contained in the layer. Preferably, it is 1 to 30 parts by mass, more preferably 3 to 25 parts by mass. When the amount of the diadamantyl diester compound used exceeds 30 parts by mass, precipitation occurs, which is not preferable. Sense The amount of use of the layer other than the optical layer containing the above bisadamantyl diester compound is also the same as described above.

The structural examples of the diadamantyl diester compound represented by the general formula (I) of the present invention are shown below. However, the compound used in the present invention is not limited thereto.

The conductive substrate 1 functions as one of the electrodes of the photoreceptor, and also serves as a support for each layer of the photoreceptor, and may have any shape such as a cylindrical shape, a plate shape, or a film shape, and the material may be aluminum or stainless steel. A metal such as nickel or a surface of glass, resin or the like is applied to a conductive processor.

The underlayer 2 is composed of a resin-based layer or a metal oxide film such as oxygen aluminum, in order to control the charge injection property of the charge from the conductive substrate to the photosensitive layer, or to cover defects on the surface of the substrate, or to enhance the photosensitive layer and The purpose of adhesion of the substrate, etc., is set as needed. The resin material used for the bottom layer is, for example, an insulating polymer such as casein, polyvinyl alcohol, polyamine, melamine or cellulose, or a conductive polymer such as polythiophene, polypyrrole or polyaniline. These resins may be used alone. Or mix and mix as appropriate. Further, these resins may contain a metal oxide such as titanium oxide or zinc oxide.

(with negatively charged laminated photoreceptor)

In the negatively charged laminated photoreceptor, the charge generating layer 4 is formed by a method of applying a coating liquid in which particles of a charge generating material are dispersed in a resin binder, and receives light to generate electric charges. Further, the charge generation efficiency is high, and the charge generated is also important for the chargeability of the charge transport layer 5, preferably low electric field dependency, and excellent injectability even under a low electric field. The charge generating material is, for example, X-type metal-free phthalocyanine, τ-type metal-free phthalocyanine, α-type oxytitanium phthalocyanine, β-type oxytitanium phthalocyanine, Y-type oxytitanium phthalocyanine, γ-type oxytitanium phthalocyanine, amorphous type. Phthalocyanine compounds such as oxytitanium phthalocyanine and ε-type copper phthalocyanine; various azo pigments, dibenzofluorenone pigments, thiopyrene pigments, anthraquinone pigments, anthrone pigments, squarylium pigments, quinacridone pigments Alternatively, these may be used singly or in appropriate combination, and a suitable substance may be selected in accordance with the light wavelength region of the exposure light source used for image formation.

The charge generating layer 4 may be any one having a charge generating function, and the film thickness is determined by the light absorption coefficient of the charge generating material, and is generally 1 μm. Next, it is preferably 0.5 μm or less. The charge generating layer is mainly composed of a charge generating material, and a charge transporting material or the like may be added to the material to be used. The resin binder is, for example, a polycarbonate resin, a polyester resin, a polyamide resin, a polyurethane resin, a vinyl chloride resin, a vinyl acetate resin, a phenoxy resin, a polyvinyl acetal resin, or a polyvinyl condensate. An aldehyde resin, a polystyrene resin, a polyfluorene resin, a diallyl phthalate resin, a polymer of a methacrylate resin, a copolymer, and the like may be used in combination as appropriate.

The charge transport layer 5 is mainly composed of a charge transport material and a resin binder. The charge transporting material may, for example, be various hydrazine compounds, styryl compounds, diamine compounds, butadiene compounds, hydrazine compounds, etc., and these may be used singly or in combination as appropriate or in combination. Further, the resin binder is, for example, various polycarbonate resins such as bisphenol A type, bisphenol Z type, bisphenol A type biphenyl copolymer, bisphenol Z type biphenyl copolymer, polyarylate resin, and poly Benzene resin, polyester resin, polyvinyl acetal resin, polyvinyl butyral resin, polyvinyl alcohol resin, vinyl chloride resin, vinyl acetate resin, polyethylene resin, polypropylene resin, acrylic resin, polyaminocarboxylic acid Ester resin, epoxy resin, melamine resin, polyoxyalkylene resin, polyamide resin, polystyrene resin, polyacetal resin, polyfluorene resin, polymer and copolymer of methacrylate, etc. They are combined individually or appropriately and mixedly. Further, a resin of the same molecular weight may be used in combination. The amount of the charge transporting material used in the charge transporting layer 5 is 50 to 90 parts by mass, preferably 3 to 30 parts by mass, per 100 parts by mass of the resin binder. Further, the content of the resin binder is preferably from 10 to 90% by mass, particularly preferably from 20 to 80% by mass, based on the solid content of the charge transport layer 5.

The charge transporting material used for the charge transporting layer 5 is, for example, as follows, but the present invention is not limited thereto.

The film thickness of the charge transport layer 5 is preferably in the range of 3 to 50 μm, more preferably in the range of 15 to 40 μm, in order to maintain a practically effective surface potential.

(single layer type photoreceptor)

In the present invention, the photosensitive layer 3 in the single layer type is mainly composed of a charge generating material, a hole transporting material, an electron transporting material (acceptor compound), and a resin binder. The charge generating material at this time may use, for example, a phthalocyanine-based pigment, an azo pigment, a dibenzofluorenone pigment, an anthraquinone pigment, an anthrone pigment, a polycyclic anthracene pigment, a squarylium pigment, a thiopyranyl pigment, a quinacridine. Ketone pigments, etc. Further, these charge generating materials may be used singly or in combination of two or more. In particular, the azo pigment of the electrophotographic photosensitive system of the present invention is preferably a diazo pigment or a trisazo pigment, and the anthraquinone pigment is preferably N,N'-bis(3,5-dimethyl). Phenyl)-3,4:9,10-fluorene-bis(carboxy quinone imine), the phthalocyanine-based pigment is preferably metal-free phthalocyanine, copper phthalocyanine or oxytitanium phthalocyanine. When using X-type metal-free phthalocyanine, τ-type metal-free phthalocyanine, ε-type copper phthalocyanine, α-type oxytitanium phthalocyanine, β-type oxytitanium phthalocyanine, Y-type oxytitanium phthalocyanine, amorphous oxytitanium phthalocyanine In the CuKα: X-ray diffraction analysis described in the specification of Japanese Patent Laid-Open No. Hei 8-209023, the specification of U.S. Patent No. 5,736, 628, and the specification of U.S. Patent No. 5,874,570, the oxytitanium phthalocyanine having a Bragg angle of 2θ of 9.6° as the maximum peak is used. In terms of sensitivity, durability and image quality, it shows a significant improvement effect. The content of the charge generating material is preferably from 0.1 to 20% by mass, more preferably from 0.5 to 10% by mass, based on the solid content of the single layer type photosensitive layer 3.

The hole transporting material may be, for example, an anthraquinone compound, a pyrazoline compound, a pyrazolone compound, an oxadiazole compound, an oxazole compound, an arylamine compound, a benzidine compound, a diphenylethylene compound, a styryl compound, or a poly- N-vinylcarbazole, polydecane, and the like. Further, these hole transporting materials may be used alone or in combination of two or more. The hole transporting material used in the present invention is preferably suitable for combination with a charge generating material, in addition to excellent transportability of a hole generated by light irradiation. The content of the hole transporting material is preferably from 3 to 80% by mass, more preferably from 5 to 60% by mass, based on the solid content of the single-layer type photosensitive layer 3.

Electron transporting materials (acceptor compounds), for example, succinic anhydride, maleic anhydride, dibromosuccinic anhydride, phthalic anhydride, 3-nitrophthalic anhydride, 4-nitrophthalic anhydride, Pyranic anhydride, pyromic acid, trimellitic acid, trimellitic anhydride, phthalimide, 4-nitrophthalimide, tetracyanoethylene, tetracyanoquinone Methane, tetrachlorine, Tetrabromide palladium, o-nitrobenzoic acid, malononitrile, trinitrofluorenone, trinitrothioxanthone, dinitrobenzene, dinitroguanidine, dinitroacridine, nitroguanidine, two A nitroguanidine, a thiopyranium compound, an anthraquinone compound, a benzoquinone compound, a diphenylguanidine compound, a naphthoquinone compound, an anthraquinone compound, a diphenylethylene anthraquinone compound, an azoquinone compound, and the like. Further, these electron transport materials may be used alone or in combination of two or more. The content of the electron transporting material is preferably from 1 to 50% by mass, more preferably from 5 to 40% by mass, based on the solid content of the single-layer type photosensitive layer 3.

As the resin binder of the single-layer photosensitive layer 3, various polycarbonate resins such as bisphenol A type, bisphenol Z type, bisphenol A type biphenyl copolymer, and bisphenol Z type biphenyl copolymer can be used. Poly stretched benzene resin, polyester resin, polyvinyl acetal resin, polyvinyl butyral resin, polyvinyl alcohol resin, vinyl chloride resin, vinyl acetate resin, polyethylene resin, polypropylene resin, acrylic resin, polyamine a polymer of an acid ester resin, an epoxy resin, a melamine resin, a polyoxyalkylene resin, a polyamide resin, a polystyrene resin, a polyacetal resin, a polyarylate resin, a polyfluorene resin, a methacrylate resin, and Copolymers, etc. Further, a resin of the same molecular weight may be used in combination.

Further, the content of the resin binder is preferably from 10 to 90% by mass, more preferably from 20 to 80% by mass, based on the solid content of the single-layer type photosensitive layer 3.

The film thickness of the single-layer photosensitive layer 3 is preferably in the range of 3 to 100 μm, more preferably in the range of 5 to 40 μm, in order to maintain a practically effective surface potential.

(Laminated photoreceptor with positive charge)

In the positively charged layered photoreceptor, the charge transport layer 5 is mainly composed of a charge transporting material and a resin binder. The charge transporting material and the resin binder can be the same as those exemplified for the charge transporting layer 5 in the negatively charged laminated photoreceptor, and are not particularly limited. Further, the content of each material and the film thickness of the charge transport layer 5 may be set to be the same as those of the negatively charged layered photoreceptor.

The charge generating layer 4 provided on the charge transporting layer 5 is mainly composed of a charge generating material, a hole transporting material, an electron transporting material (acceptor compound), and a resin binder. The charge generating material, the hole transporting material, the electron transporting material, and the resin binder can be the same as those exemplified for the single layer type photosensitive layer 3 in the single layer type photoreceptor, and are not particularly limited. Further, the content of each material and the film thickness of the charge generating layer 4 may be set to be the same as those of the single layer type photosensitive layer 3 in the single layer type photoreceptor.

In the present invention, in the underlayer 2, the photosensitive layer 3, the charge generating layer 4, and the charge transporting layer 5, the sensitivity is improved, the residual potential is reduced, or the stability against environmental or harmful light is improved, and the abrasion resistance is included. Various additives can be used as necessary for the improvement of durability. Additives In addition to the compounds of the general formula (I) of the present invention, succinic anhydride, maleic anhydride, dibromosuccinic anhydride, pyrogalic anhydride, pyroghuric acid, trimellitic acid, trimellitic anhydride may be used. , o-phthalimide, 4-nitrophthalimide, tetracyanoethylene, tetracyanoquinodimethane, tetrachloro-palladium, tetrabromo-p-quinone, o-nitrobenzoic acid, three A compound such as nitrofluorenone. Further, an anti-deterioration agent such as an antioxidant or a light stabilizer may be added. Compounds used for such purposes, such as benzohydropyranol derivatives having tocopherols and the like And an ether compound, an ester compound, a polyaralkyl compound, a hydroquinone derivative, a diether compound, a benzophenone derivative, a benzotriazole derivative, a thioether compound, a phenylenediamine derivative, a phosphonate, The phosphite, the phenol compound, the hindered phenol compound, the linear amine compound, the cyclic amine compound, the hindered amine compound, and the like are not limited thereto.

Further, in the photosensitive layer, a flattening agent such as eucalyptus oil or fluorine-based oil may be contained in order to improve the flatness of the formed film and impart further lubricity. Further, in order to adjust the film hardness, reduce the friction coefficient, and impart lubricity, it may contain a metal oxide such as cerium oxide ( vermiculite), titanium oxide, zinc oxide, calcium oxide, aluminum oxide (alumina), or zirconia, and sulfuric acid. A metal sulfide such as barium or calcium sulfate; a fine particle of a metal nitride such as tantalum nitride or aluminum nitride; a fluorine-based resin particle such as tetrafluoroethylene; or a fluorine-based comb-type graft polymer. Further, other generally known additives may be included as far as possible, within the scope of not significantly impairing the electrophotographic characteristics.

Further, the present invention is applied to the surface of the photosensitive layer, and in order to further improve environmental resistance and mechanical strength, the surface protective layer 6 may be provided as necessary. The surface protective layer 6 is preferably made of a material excellent in durability against mechanical stress and environmental resistance, and has a property of penetrating light induced by the charge generating layer with low loss as much as possible.

The surface protective layer 6 is composed of a layer mainly composed of a resin binder or an inorganic film such as amorphous carbon. In addition, the resin binder may contain cerium oxide ( vermiculite), titanium oxide, zinc oxide, calcium oxide, aluminum oxide (alumina), zirconia, or the like in order to improve conductivity, reduce friction coefficient, and impart lubricity. Metal oxides, nitrogen oxides such as metal oxides, barium sulfate, calcium sulfate, etc. A metal nitride such as ruthenium or aluminum nitride or a fine particle of a metal oxide, or a fluorine-based resin such as tetrafluoroethylene or a fluorine-based comb-type graft polymer resin.

In the surface protective layer 6, the compound represented by the above general formula (I) of the present invention can be used in order to improve the abrasion resistance or suppress the inflow and outflow of gas or vapor. Further, in order to impart charge transportability, a charge transporting substance or an electron accepting substance used for the photosensitive layer may be contained, or a flattening agent such as eucalyptus oil or fluorine-based oil may be contained in order to improve the flatness of the formed film or impart lubricity.

Although the film thickness of the surface protective layer 6 itself depends on the composition of the surface protective layer, it can be arbitrarily set within a range in which repeated effects such as an increase in residual potential are not caused.

When the photoreceptor of the present invention is produced, the coating liquid for forming each layer constituting the photoreceptor contains the bisadamantyl diester compound represented by the above general formula (I). The coating liquid can be applied to various coating methods such as a dip coating method or a spray coating method, and is not limited to any coating method.

(electrophotographic device)

The photoreceptor for electrophotography of the present invention can be used in various machine programs to obtain desired effects. Specifically, it is a contact charging method using a roller or a brush, a charging process using a non-contact charging method such as a discharge tube or a charging tube, and a contact method using a non-magnetic single component, a magnetic single component, and a two-component developing method. A sufficient effect can be obtained by a developing program such as development and non-contact development.

As an example, Fig. 2 is a view showing the outline of the electrophotographic apparatus of the present invention. Make up the picture. In the electrophotographic apparatus 60 shown in the drawing, the electrophotographic photoreceptor 7 of the present invention comprising the conductive substrate 1 and the underlayer 2 and the photosensitive layer 300 coated on the outer peripheral surface thereof is mounted. Further, this electrophotographic apparatus 60 is composed of a roller charging member 21 disposed at the outer peripheral portion of the photoreceptor 7, a high-voltage power source 22 that supplies an applied voltage to the roller charging member 21, an image forming member 23, and a developing roller 241. The paper 24, the paper feed member 25 including the paper feed roller 251 and the paper feed guide 252, the transfer charger (direct charge type) 26, the cleaning device 27 including the cleaning blade 271, and the static eliminating member 28 may be formed in color. Printer.

Example

The invention will be described in more detail below using examples.

Synthesis example

Under a stream of Ar, in a 1000 ml three-necked flask, 10.0 g of di-methanol and 15.8 g of pyridine were dissolved in 150 ml of dehydrated tetrahydrofuran (THF) at room temperature, using a dropping funnel at 140 ml. A solution of 25.0 g of 1-adamantanecarboxylic acid dissolved in dehydrated THF was dropped. After the dropwise addition, the mixture was reacted at 50 ° C for 8 hours, and after cooling to room temperature, the reaction solution was washed with 300 ml of ion-exchanged water for 3 times, and then recrystallized three times to obtain the desired formula (I-1). 29.5 g of the compound shown (NMR analysis result (structural isomer: 73/27)).

The obtained compound was analyzed by NMR spectroscopy, mass spectrometry, infrared Machine analysis such as line spectroscopic analysis confirms the structure. The obtained NMR spectrum of the compound is represented by the formula (I-1) as shown in Fig. 3.

<Production Example of Photoreceptor with Negatively Conductive Lamination> Example 1

5 parts by mass of alcohol-soluble nylon (trade name "Amilan CM8000", manufactured by Toray Co., Ltd.) and 5 parts by mass of the aminosilane-treated titanium oxide fine particles were dissolved and dispersed in 90 parts by mass of methanol to prepare a coating liquid. Dip coating on the outer diameter of the conductive substrate The outer circumference of a 30 mm aluminum cylinder was dried at a temperature of 100 ° C for 30 minutes to form a bottom layer having a film thickness of about 2 μm.

1.5 parts by mass of Y-type oxytitanium phthalocyanine described in the specification of Japanese Patent Laid-Open No. 64-17066 or No. 4898799, and a polyvinyl butyral as a resin binder (trade name " 1.5 parts by mass of S-LEC B BX-1", manufactured by Sekisui Chemical Co., Ltd., prepared by dispersing for 1 hour in a sanding disperser in 60 parts by mass of an equal mixture of dichloromethane and dichloroethane. The coating liquid was dip-coated on the above-mentioned underlayer, and dried at a temperature of 80 ° C for 30 minutes to form a charge generating layer having a film thickness of about 0.3 μm.

100 parts by mass of the compound represented by the above structural formula (II-1) as a charge transporting material, and a polycarbonate resin (trade name "Panlite TS-2050", manufactured by Teijin Chemical Co., Ltd.) 100 as a resin binder. After dissolving 900 parts by mass of methylene chloride, 0.1 parts by mass of eucalyptus oil (KP-340, manufactured by Shin-Etsu Polymer Co., Ltd.) was added, and then the compound represented by the above formula (I-1) was further added. 10 parts by mass of the coating liquid was prepared, and the coating liquid was applied onto the charge generating layer, and dried at a temperature of 90 ° C for 60 minutes to form a charge transport layer having a film thickness of about 25 μm to prepare a photoreceptor for electrophotography.

Example 2~75

A photoreceptor for electrophotography was produced in the same manner as in Example 1 except that the compound represented by the above formula (I-1) was changed to the compound represented by the above formula (I-2) to (I-75).

Example 76

A photoreceptor for electrophotography was produced in the same manner as in Example 1 except that the amount of the compound represented by the above formula (I-1) was changed to 1.0 part by mass.

Example 77

A photoreceptor for electrophotography was produced in the same manner as in Example 1 except that the amount of the compound represented by the above formula (I-1) was changed to 3.0 parts by mass.

Example 78

A photoreceptor for electrophotography was produced in the same manner as in Example 1 except that the amount of the compound represented by the above formula (I-1) was changed to 6.0 parts by mass.

Example 79

The compound of the above formula (I-1) was added in the same manner as in Example 1 except that 3.0 parts by mass of the compound was added to the charge transport layer. It is used as a photoreceptor for electrophotography.

Example 80

An electrophotographic photoreceptor was produced in the same manner as in Example 1 except that the compound represented by the above formula (I-1) was added to the charge transporting layer instead of the charge transporting layer.

Example 81

The charge transport layer was formed in the same manner as in Example 1 except that the compound represented by the above formula (I-1) and eucalyptus oil were removed from the coating liquid for a charge transport layer used in Example 1, and a charge transport layer was formed to have a film thickness of 20 μm. . Then, 80 parts by mass of the compound represented by the above structural formula (II-1) as a charge transporting material, and a polycarbonate resin as a resin binder (trade name "PCZ-500", Mitsubishi Gas Chemistry ( After 120 parts by mass of the product was dissolved in 900 parts by mass of methylene chloride, 0.1 parts by mass of eucalyptus oil (KP-340, manufactured by Shin-Etsu Polymer Co., Ltd.) was added, and then the compound 12 represented by the above formula (I-1) was further added. The coating liquid prepared by the mass fraction was formed into a film, and dried at a temperature of 90 ° C for 60 minutes to form a surface protective layer having a film thickness of about 10 μm to prepare a photoreceptor for electrophotography.

Example 82

In the same manner as in Example 1, except that the compound represented by the above formula (I-1) was added to the undercharge layer without adding 3.0 parts by mass to the underlayer, and 1.0 part by mass of the charge generating layer was added. Photoreceptor .

Example 83

In addition, when the compound represented by the above formula (I-1) is added in an amount of 3.0 parts by mass to the underlayer, and the amount of the compound represented by the above formula (I-1) in the charge transporting layer is 3.0 parts by mass, In the same manner as in Example 1, a photoreceptor for electrophotography was produced.

Example 84

In addition, when the compound represented by the above formula (I-1) is added in an amount of 3.0 parts by mass to the charge generating layer, and the amount of the compound represented by the above formula (I-1) in the charge transporting layer is 3.0 parts by mass, A photoreceptor for electrophotography was produced in the same manner as in Example 1.

Example 85

Addition of 3.0 parts by mass of the compound of the above formula (I-1) to the underlayer and addition of 1.0 part by mass to the charge generating layer, and addition of the compound of the above formula (I-1) in the charge transporting layer A photoreceptor for electrophotography was produced in the same manner as in Example 1 except that the amount was 3.0 parts by mass.

Example 86

An electrophotographic photograph was produced in the same manner as in Example 1 except that the charge generating material used in Example 1 was changed to the α-type oxytitanium phthalocyanine described in the specification of JP-A-61-217050 or the specification of US Pat. No. 4,728,592. The photoreceptor is used in combination.

Example 87

An electrophotographic photoreceptor was produced in the same manner as in Example 1 except that the charge-generating material used in Example 1 was changed to X-type metal-free phthalocyanine (manufactured by Dainippon Ink and Chemicals, Fastogen Blue 8120B).

Comparative example 1

A photoreceptor for electrophotography was produced in the same manner as in Example 1 except that the compound represented by the above formula (I-1) was not added to the charge transport layer.

Comparative example 2

An electrophotographic apparatus was produced in the same manner as in Example 1 except that the compound represented by the above formula (I-1) was not added to the charge transporting layer, and the amount of the resin binder for the charge transporting layer was increased to 110 parts by mass. Use a photoreceptor.

Comparative example 3

In the charge transporting layer, the compound represented by the above formula (I-1) was not added, and 10 parts by mass of dioctyl phthalate (manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the same procedure as in Example 1 was carried out. Photoreceptor for electrophotography.

Comparative example 4

A photoreceptor for electrophotography was produced in the same manner as in Example 83 except that the compound represented by the above formula (I-1) was not used.

Comparative Example 5

A photoreceptor for electrophotography was produced in the same manner as in Example 84 except that the compound represented by the above formula (I-1) was not used.

The photoreceptors produced in the above Examples 1 to 87 and Comparative Examples 1 to 5 were mounted on LJ4250 manufactured by HP Co., Ltd., and evaluated by the following method. In other words, first, the surface of the photoreceptor was charged to 650 V by corona discharge in a dark place, and then the surface potential V0 immediately after charging was measured. Then, the photoreceptor was allowed to stand in the dark for 5 seconds, and the surface potential V5 was measured, and the potential retention ratio Vk5 (%) after charging for 5 seconds was obtained by the following formula.

Vk5=V5/V0×100

Next, using a halogen lamp as a light source, an exposure light source that is split by a filter to 780 nm is used, and the photoreceptor is irradiated for 5 seconds from the time when the surface potential becomes -600 V, and the light is attenuated until the surface potential becomes -300 V. The exposure amount was E1/2 (μJcm ^-2 ), and the light amount obtained was attenuated until the surface potential became -50 V as the sensitivity E50 (μJcm ^-2 ).

Further, in the ozone exposure apparatus in which the photoreceptor can be placed in an ozone atmosphere, the photoreceptors prepared in the above Examples 1 to 87 and Comparative Examples 1 to 5 were placed, and after ozone exposure at 100 ppm for 2 hours, the above potential retention was measured again. Rate, the degree of change of the retention rate Vk5 before and after ozone exposure was determined, and the rate of change in ozone exposure (ΔVk5) was expressed as a percentage. When the retention rate before ozone exposure is regarded as Vk5 ₁ and the retention rate after ozone exposure is regarded as Vk _{5 2} , the rate of change in ozone exposure retention can be obtained by the following formula.

△Vk5=Vk5 ₂ (after ozone exposure)/Vk5 ₁ (before ozone exposure)

The electrical characteristics of the photoreceptors produced in Examples 1 to 87 and Comparative Examples 1 to 5, which are the results of the above measurement, are shown in the following table.

From the results in the above table, it is understood that even when the compound of the present invention is used as an additive constituting each layer of the photoreceptor, the initial electrical characteristics are not greatly affected, and the change in the retention ratio before and after the ozone exposure can be suppressed.

Further, in Comparative Example 2 in which the amount of the resin binder used for the charge transporting layer was increased to replace the compound of the present invention, the sensitivity was somewhat slowed down. And the retention rate before and after ozone exposure varies greatly. From this, it is understood that the effect of using only the compound of the present invention cannot be obtained by merely increasing the amount of the resin binder used in the charge transporting layer.

Further, even if the phthalocyanine as the charge generating material is changed, the fluctuation of the initial sensitivity of the large amount obtained by using the compound of the present invention is hardly observed, and the fluctuation of the retention ratio before and after the ozone exposure can be suppressed.

Then, the photoreceptor produced in the above-mentioned Examples 1 to 87 and Comparative Examples 1 to 5 was mounted on a digital photocopier (Image Runner Color 2880, manufactured by Canon Co., Ltd.), which was modified into a two-component development method capable of measuring the surface potential of the photoreceptor. In the evaluation of the potential stability of the photocopying machine before and after printing 100,000 sheets, the image memory and the amount of filming caused by the friction between the photosensitive layer and the paper or the blade. The results are shown in the following tables.

The image evaluation is performed by applying the checkered flag in the first half and the printing evaluation of the halftone image sample in the latter half, by evaluating the presence or absence of the memory phenomenon in which the checkered flag is mapped to the halftone portion. As a result, those who did not observe the memory phenomenon were ○, those who observed the memory phenomenon slightly were △, and those who clearly observed the memory phenomenon were ×, and those who judged the shading and the original image were judged as (positive), shading and original map. On the contrary, the person who appears to flip the image is judged as (negative).

From the results in the above table, it is understood that by adding the compound of the present invention to each layer, there is no significant difference in initial electromechanical properties compared to when it is not added, and the amount of film removal after repeated printing of 100,000 sheets can be reduced. above 50. In addition, at this time, no problem was found in the potential and image evaluation after printing.

Next, the potential characteristics of the photoreceptor in each use environment from low temperature and low humidity to high temperature and high humidity were investigated by the above-described digital photocopier, and image evaluation was also carried out. The results are shown in the table below.

From the results in the above table, it is understood that by using the compound of the present invention, the dependence of the potential or the image on the environment can be lowered, and in particular, the memory under low temperature and low humidity can be greatly improved.

<Production Example of Positively Charged Single Layer Photoreceptor> Example 88

5 parts by mass of an alcohol-soluble nylon (trade name "Amilan CM8000", manufactured by Toray Co., Ltd.) and 5 parts by mass of a titanium oxide fine particle treated with an amino decane dissolved in a coating liquid prepared by dissolving and dispersing 90 parts by mass of methanol, and dip-coating Between the outer diameter of the conductive substrate The outer circumference of a 24 mm aluminum cylinder was dried at a temperature of 100 ° C for 30 minutes to form a bottom layer having a film thickness of about 2 μm.

7.0 parts by mass of the styryl compound represented by the above structural formula (II-12) as a hole transporting substance, and 3 parts by mass of a compound represented by the following formula (III-1) as an electron transporting substance, as a resin 9.6 parts by mass of a polycarbonate resin (trade name "Panlite TS-2050", manufactured by Teijin Chemicals Co., Ltd.), 0.04 parts by mass of oyster sauce (KF-54, Shin-Etsu Polymer Co., Ltd.), and the above formula 1.5 parts by mass of the compound of the formula (I-1), dissolved in 100 parts by mass of methyl chloride, and 0.3 parts by mass of the X-type metal phthalocyanine described in the specification of the US Pat. No. 3357989, which is a charge generating material, is added. The coating liquid was prepared by dispersion treatment by a sanding disperser. Using this coating liquid, a coating film was formed on the above-mentioned underlayer, and dried at a temperature of 100 ° C for 60 minutes to form a single-layer photosensitive layer having a film thickness of about 25 μm to obtain a positively-charged single-layer type electrophotographic photoconductor.

Examples 89~92

The compound represented by the above formula (I-1) used in Example 88 was changed to the above formula (I-2), (I-21), (I-29), and (I-37). A photoreceptor for electrophotography was produced in the same manner as in Example 89 except for the compound.

Comparative Example 6

A photoreceptor for electrophotography was produced in the same manner as in Example 88 except that the compound represented by the above formula (I-1) was not used.

Comparative Example 7

An electrophotographic sensitization was carried out in the same manner as in Example 88 except that the compound of the above formula (I-1) used in Example 88 was changed to dioctyl phthalate (manufactured by Wako Pure Chemical Industries, Ltd.). body.

The photoreceptors produced in the above Examples 88 to 92 and Comparative Examples 6 and 7 were evaluated by the following methods. That is, first, the surface of the photoreceptor was charged with a surface electric potential V ₀ after being charged by corona discharge in a dark place. Then, the photoreceptor was allowed to stand in the dark for 5 seconds, and the surface potential V5 was measured, and the potential retention ratio Vk5 (%) after charging for 5 seconds was obtained by the following formula.

Vk5=V5/V0×100

Next, using a halogen lamp as a light source, an exposure light source of 1.0 μW/cm ² using a filter to be split at 780 nm was used, and the photoreceptor was irradiated for 5 seconds from the time when the surface potential became +600 V, and the light was attenuated until The exposure amount required for the surface potential to be +300 V was taken as E1/2 (μJcm ^-2 ), and the amount of exposure required until the surface potential became +50 V was obtained as the sensitivity E50 (μJcm ^-2 ).

Further, in the ozone exposure apparatus in which the photoreceptor can be placed in an ozone atmosphere, the photoreceptors prepared in the above Examples 88 to 92 and Comparative Examples 6 and 7 were placed, and after ozone exposure at 100 ppm for 2 hours, the above potential retention was measured again. Rate, the degree of change of the retention rate Vk5 before and after ozone exposure was determined, and the rate of change in ozone exposure (ΔVk5) was expressed as a percentage. When the retention rate before ozone exposure is Vk5 ₁ and the retention ratio after ozone exposure is Vk5 ₂ , the rate of change in ozone exposure retention can be obtained by the following formula.

△Vk5=Vk5 ₂ (after ozone exposure)/Vk5 ₁ (before ozone exposure)

The above table shows the electrical characteristics of the photoreceptors produced in Examples 88 to 92 and Comparative Examples 6 and 7 which showed the above measurement results.

From the results in the above table, it is understood that even if the compound of the present invention is used as an additive in each layer, the initial electrical characteristics are not greatly affected, and the change in the retention ratio before and after the ozone exposure can be suppressed.

Next, the photoreceptors prepared in Examples 88 to 92 and Comparative Examples 6 and 7 were prepared. It is mounted on Brother's printer HL-2040, which can be used to measure the surface potential of the photoreceptor. It evaluates the potential stability, image memory, and photosensitive layer and paper or scraping of the printer before and after printing 10,000 sheets. The amount of filming caused by the friction of the sheet. The results are shown in the table below.

The image evaluation system applies the checkered flag pattern in the first half and the print evaluation of the image sample in the second half to the halftone pattern, by reading the memory phenomenon of the halftone portion mapped to the square flag. Perform image evaluation. Those who did not observe the memory phenomenon were ○, those who observed the memory phenomenon slightly were △, those who clearly observed the memory phenomenon were ×, and those who showed the same brightness as the original image were judged as (positive), and the shade was opposite to the original image. That is, the person who appears to flip the image is judged to be (negative).

From the results in the above table, it is understood that by adding the compound of the present invention to each layer, there is no significant difference in the initial electromechanical properties compared to the case where it is not added, and the amount of film after repeated printing of 10,000 sheets can be obtained. Reduce by more than 50%. Further, at this time, no problem was observed in the potential and image evaluation after printing.

Next, investigate from low temperature and low humidity to high temperature and high humidity by the above printer. The potential characteristics of the photoreceptor in each use environment were also evaluated. The results are shown in the table below.

From the results in the above table, it is understood that by using the compound of the present invention, the potential or the dependence of the image on the environment can be lowered, and in particular, the memory phenomenon under low temperature and low humidity can be greatly improved.

<Manufacture of positively charged laminated photoreceptor> Example 93

50 parts by mass of the compound represented by the above formula (II-15) as a charge transporting material, and 50 parts by mass of a polycarbonate resin (trade name "Panlite TS-2050", manufactured by Teijin Chemical Co., Ltd.) as a resin binder 1.5 parts by mass of the compound represented by the above formula (I-1) was dissolved in 800 parts by mass of dichloromethane to prepare a coating liquid. The coating liquid is dip-coated on the outer diameter as a conductive substrate The outer circumference of a 24 mm aluminum cylinder was dried at a temperature of 120 ° C for 60 minutes to form a charge transport layer having a film thickness of 15 μm.

1.5 parts by mass of the X-type metal-free phthalocyanine described in the specification of the U.S. Patent No. 3,357,989, which is a charge-generating material, and 10 parts by mass of the diphenylethylene compound represented by the above formula (II-15) as a hole transporting material. 25 parts by mass of the compound represented by the above formula (III-1) as an electron transporting material, and 60 parts by mass of a polycarbonate resin (trade name "Panlite TS-2050", manufactured by Teijin Chemicals Co., Ltd.) as a resin binder. Dissolved and dispersed in 800 parts by mass of 1,2-dichloroethane to prepare a coating liquid, and the coating liquid was dip-coated on the charge transport layer, and dried at a temperature of 100 ° C for 60 minutes to form a charge generating layer having a film thickness of 15 μm. A positively charged laminated photoreceptor is produced.

Example 94

50 parts by mass of the compound represented by the above formula (II-15) as a charge transporting material, and 50 parts by mass of a polycarbonate resin (trade name "Panlite TS-2050", manufactured by Teijin Chemical Co., Ltd.) as a resin binder The solution was prepared by dissolving in 800 parts by mass of dichloromethane. The coating liquid is dip-coated on the outer diameter as a conductive substrate The outer circumference of a 24 mm aluminum cylinder was dried at a temperature of 120 ° C for 60 minutes to form a charge transport layer having a film thickness of 15 μm.

1.5 parts by mass of the X-type metal-free phthalocyanine described in the specification of the U.S. Patent No. 3,357,989, which is a charge-generating material, and 10 parts by mass of the diphenylethylene compound represented by the above formula (II-15) as a hole transporting material. 25 parts by mass of the compound represented by the above formula (III-1) as an electron transporting material, and 60 parts by mass of a polycarbonate resin (trade name "Panlite TS-2050", manufactured by Teijin Chemicals Co., Ltd.) as a resin binder. And 1.5 parts by mass of the compound represented by the above formula (I-1), dissolved and dispersed in the mass of 1,2-dichloroethane 800 In the portion, the coating liquid was prepared, and the coating liquid was dip-coated on the charge transport layer, and dried at a temperature of 100 ° C for 60 minutes to form a charge generating layer having a film thickness of 15 μm to prepare a positively chargeable layered photoreceptor.

Example 95

50 parts by mass of the compound represented by the above formula (II-15) as a charge transporting material, and 50 parts by mass of a polycarbonate resin (trade name "Panlite TS-2050", manufactured by Teijin Chemicals Co., Ltd.) as a resin binder 1.5 parts by mass of the compound represented by the above formula (I-1) was dissolved in 800 parts by mass of dichloromethane to prepare a coating liquid. The coating liquid is dip coated on the outer diameter as a conductive substrate The outer circumference of a 24 mm aluminum cylinder was dried at a temperature of 120 ° C for 60 minutes to form a charge transport layer having a film thickness of 15 μm.

1.5 parts by mass of the X-type metal-free phthalocyanine described in the specification of the U.S. Patent No. 3,357,989, which is a charge-generating material, and 10 parts by mass of the diphenylethylene compound represented by the above formula (II-15) as a hole transporting material. 25 parts by mass of the compound represented by the above formula (III-1) as an electron transporting material, and 60 parts by mass of a polycarbonate resin (trade name "Panlite TS-2050", manufactured by Teijin Chemicals Co., Ltd.) as a resin binder. And 1.5 parts by mass of the compound represented by the above formula (I-1), dissolved and dispersed in 800 parts by mass of 1,2-dichloroethane to prepare a coating liquid, and the coating liquid is dip-coated on the charge transport layer. The film was dried at a temperature of 100 ° C for 60 minutes to form a charge generating layer having a film thickness of 15 μm to prepare a positively chargeable layered photoreceptor.

Comparative Example 8

A photoreceptor for electrophotography was produced in the same manner as in Example 93 except that the compound represented by the above formula (I-1) was not used.

Comparative Example 9

An electrophotographic photosensitive film was produced in the same manner as in Example 95 except that the compound of the above formula (I-1) used in Example 95 was changed to dioctyl phthalate (manufactured by Wako Pure Chemical Industries, Ltd.). body.

The photoreceptors produced in the above Examples 93 to 95 and Comparative Examples 8 and 9 were evaluated by the same method as in Example 92 and the like.

The electrical characteristics of the photoreceptors produced in Examples 93 to 95 and Comparative Examples 8 and 9 of the above measurement results are shown in the following table.

From the results in the above table, it is understood that even when the compound of the present invention is used as an additive as an additive, the initial electrical characteristics are not greatly affected, and the change in the retention ratio before and after the ozone exposure can be suppressed.

Next, the sensitizations produced in Examples 93 to 95 and Comparative Examples 8 and 9 were carried out. The body is mounted in a modified surface to measure the surface potential of the photoreceptor. The printer HL-2040 manufactured by Brother Inc. prints potential stability, image memory, and photosensitive layer and paper for 10,000 sheets of printers. Or the amount of film shaving caused by the friction of the blade was evaluated. The results are shown in the table below.

The image evaluation was carried out by the same method as in Example 92 and the like.

From the results in the above table, it is understood that by adding the compound of the present invention to each layer, there is no significant difference in initial electromechanical properties compared to when it is not added, and the amount of film removal after repeated printing of 10,000 sheets can be reduced. above 50. Further, at this time, no problem was observed in the potential and image evaluation after printing.

Then, the potential characteristics of the photoreceptor in each use environment from low temperature and low humidity to high temperature and high humidity were investigated by the above-mentioned printer, and image evaluation was also carried out. The results are shown in the table below.

From the results in the above table, it is understood that by using the compound of the present invention, the potential or the dependence of the image on the environment can be lowered, and in particular, the memory phenomenon under low temperature and low humidity can be greatly improved.

As described above, the photoreceptor for electrophotography of the present invention can exhibit sufficient effects in various charging programs, development programs, and various programs for negatively charged programs and positively charged programs for photoreceptors. According to the present invention, it is confirmed that the electrophotographic characteristics of the electrophotographic photoreceptor are stabilized by the use of a specific compound as an additive at the initial stage, at the time of repeated use, and when the environmental conditions are changed, even under various conditions. A photoreceptor for electrophotography which does not cause image damage such as image memory.

1‧‧‧Electrically conductive substrate

2‧‧‧ bottom layer

3‧‧‧Photosensitive layer

4‧‧‧ Charge generation layer

5‧‧‧Charge transport layer

6‧‧‧Surface protection layer

21‧‧‧ Roller live parts

22‧‧‧High voltage power supply

23‧‧‧Image exposure components

24‧‧‧developer

241‧‧‧developing roller

25‧‧‧Paper supply components

251‧‧‧paper feed roller

252‧‧‧paper guides

26‧‧‧Transfer electrical appliances (direct charging type)

27‧‧‧ cleaning device

271‧‧‧ cleaning blade

28‧‧‧Electrical components

60‧‧‧Electronic camera

300‧‧‧Photosensitive layer

[ Fig. 1] Fig. 1 (a) is a schematic cross-sectional view showing an example of a photoreceptor for electrophotographic separation-separating type electrophotography according to the present invention, and (b) is a photoreceptor for positively charged single-layer type electrophotography of the present invention. (C) is a schematic cross-sectional view showing an example of a photoreceptor for positive-charge functional separation-separating electrophotographic according to the present invention.

Fig. 2 is a schematic view showing an example of an electrophotographic apparatus of the present invention. Mapping.

Fig. 3 shows an NMR spectrum of a compound represented by the formula (I-1).

Claims (10)

A photoreceptor for electrophotography, which is a photoreceptor for electrophotography having at least a photosensitive layer on a conductive substrate, characterized in that the photosensitive layer contains a bisadamantyl diester compound represented by the following general formula (I). (In the general formula (I), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted carbon number of 1 to 6 Alkoxy group, aryl or heterocyclic group having 6 to 20 carbon atoms, each of l, m and n is an integer of 1 to 4, and U and W represent a single bond or a substituted or unsubstituted carbon number of 1 to 6 The alkyl group, V system represents an OCO group or a COO group). A photoreceptor for electrophotography which is a photoreceptor for electrophotography having at least a bottom layer on a conductive substrate, characterized in that the underlayer contains a diadamantyl diester compound represented by the following general formula (I). (In the general formula (I), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted carbon number of 1 to 6 Alkoxy group, aryl or heterocyclic group having 6 to 20 carbon atoms, each of l, m and n is an integer of 1 to 4, and U and W represent a single bond or a substituted or unsubstituted carbon number of 1 to 6 The alkyl group, V system represents an OCO group or a COO group). A photoreceptor for electrophotography, which is a photoreceptor for electrophotography having at least a charge generating layer on a conductive substrate, characterized in that the charge generating layer contains a bisadamantyl diester compound represented by the following general formula (I) , (In the general formula (I), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted carbon number of 1 to 6 Alkoxy group, aryl or heterocyclic group having 6 to 20 carbon atoms, each of l, m and n is an integer of 1 to 4, and U and W represent a single bond or a substituted or unsubstituted carbon number of 1 to 6 The alkyl group, V system represents an OCO group or a COO group). A photoreceptor for electrophotography, which is a photoreceptor for electrophotography having at least a charge transporting layer on a conductive substrate, characterized in that the charge transporting layer contains a diadamantyl diester compound represented by the following general formula (I) , (In the general formula (I), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted carbon number of 1 to 6 Alkoxy group, aryl or heterocyclic group having 6 to 20 carbon atoms, each of l, m and n is an integer of 1 to 4, and U and W represent a single bond or a substituted or unsubstituted carbon number of 1 to 6 The alkyl group, V system represents an OCO group or a COO group). A photoreceptor for electrophotography, which is a photoreceptor for electrophotography having at least a surface protective layer on a conductive substrate, characterized in that the surface protective layer contains a bisadamantyl diester compound represented by the following general formula (I) , (In the general formula (I), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted carbon number of 1 to 6 Alkoxy group, aryl or heterocyclic group having 6 to 20 carbon atoms, each of l, m and n is an integer of 1 to 4, and U and W represent a single bond or a substituted or unsubstituted carbon number of 1 to 6 The alkyl group, V system represents an OCO group or a COO group). The photoreceptor for electrophotography according to the first aspect of the invention, wherein the photosensitive layer is a positively charged single layer type. The photoreceptor for electrophotography according to the first aspect of the invention, wherein the photosensitive layer is a positively charged layered type. The photoreceptor for electrophotography according to any one of claims 1 to 5, wherein the bisadamantyl diester compound has a structure represented by the following formula (I-1). The photoreceptor for electrophotography according to any one of claims 1 to 5, wherein the amount of the bisadamantyl diester compound added is a resin contained in the layer containing the diadamantyl diester compound. 100 parts by mass of the binder is 30 parts by mass or less. A method for producing a photoreceptor for electrophotography, which comprises a step of applying a coating liquid forming layer to a conductive substrate, wherein the coating liquid contains the following general formula (I) represents a diadamantyl diester compound, (In the general formula (I), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted carbon number of 1 to 6 Alkoxy group, aryl or heterocyclic group having 6 to 20 carbon atoms, each of l, m and n is an integer of 1 to 4, and U and W represent a single bond or a substituted or unsubstituted carbon number of 1 to 6 The alkyl group, V system represents an OCO group or a COO group).